That article showed, in 17 cases of very preterm infants who had PVHD which had reached the 97th percentile, that wave latencies on the evoked potentials and aEEG suppression were both increased. When the infants had shunts inserted these features returned to normal.

The standard indication (as I noted above there is no real standardization here) is to intervene when the ventricular width is more than 4 mm above the 97th percentile, this threshold arose somewhat arbitrarily in the 1980’s, and provides a benchmark against which to compare other approaches. Ten of the patients in this new study were below that cut off, yet still showed the neurophysiologic changes, with the evoked potential changes being more reliably affected.

Dr de Vries editorial was written to address the specific issues in the Klebermass article, she notes that they have not consistently found the same aEEG changes in her unit, but that they have noted prolongation of the visual evoked potential wave latencies.

We will hopefully soon have better information on which to base our interventions, the European study called ELVIS (early versus late ventricular intervention study) is an RCT comparing intervention at the standard threshold that I have described (which is the ‘late arm) to intervention once the ventricles are over the 97th percentile. Until those results are in it looks like visual evoked potentials may give us some idea of which babies have cerebral dysfunction from their PVHD.